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To provide a basis for promising exosome-based therapies against intervertebral disc degeneration (IDD), our present research aimed to identify a mechanism underlying the vesicle release from nucleus pulposus cells (NPCs). Scutellarin (SC) is a natural chemotherapeutic agent isolated from Erigeron breviscapus with a variety of biological activities. Here, we observed the significantly elevated autophagy levels in rat NPCs under the stimulation of SC, leading to a concomitant enhancement of intracellular vesicle release, which could be attributed to the inactivation of the phosphoinositide 3-kinase (PI3K)/phosphatase and tensin homolog (PTEN)/protein kinase B (Akt) pathway. To ensure that exosome release was driven by SC via the autophagic pathway, we implemented gain-of-function and loss-of-function studies by additionally using insulin-like growth factor-1 (IGF-1) and small-interfering RNA of autophagy-related gene 5 (ATG5), and the exosome secretion decreased in the case of attenuated autophagy. Evidently, the treatment with SC exerted the remarkable upregulation of Rab8a through the overexpression of ATG5. After the respective knockdown of ATG5 and Rab8a, the increased release of exosomes induced by SC was reversed, whereas the number of intracellular vesicles was restored. Overall, it can be concluded that SC contributes to the autophagy activation in NPCs by acting on the PI3K/PTEN/Akt pathway, which upregulates the expression of Rab8a and promotes the release of exosomes, inspiring novel therapeutic strategies in preventing IDD that might be fruitfully investigated.

Oxidative stress can lead to nucleus pulposus cell (NPC) apoptosis, which is considered to be one of the main contributors to intervertebral disc degeneration (IVDD). Procyanidin B2 is a natural antioxidant that protects against oxidative stress. However, whether procyanidin B2 protects NPCs from oxidative stress remains unknown. In this study, we demonstrated that procyanidin B2 could reduce tert-butyl hydroperoxide-induced reactive oxygen species in rat NPCs and attenuate rat NPC apoptosis. Further experiments revealed that procyanidin B2 upregulated the expression of both nuclear factor erythroid 2-related factor 2 (Nrf2) and phosphorylation of protein kinase B (Akt). We then used silencing of Nrf2 and LY294002 to silence Nrf2 expression and block the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, respectively, and found that the protective roles of procyanidin B2 in NPCs were inhibited. Therefore, we demonstrated that procyanidin B2 alleviated rat NPC apoptosis induced by oxidative stress by upregulating Nrf2 via activation of the PI3K/Akt signaling pathway. This study provides a potential therapeutic approach for procyanidin B2 in IVDD, which might help in the development of new drugs for IVDD treatment.

re is paucity in the literature on the epidemiological evidence of pulmonary thromboembolism (PE) and deep venous thrombosis (DVT) in spinal metastatic tumor patients. The aim of our study was to identify the incidence and risk factors for VTE in spinal metastasis patients treated with decompression with internal instruments.We prospectively investigated the occurrence of VTE after decompression with internal fixations in 80 spinal metastasis patients. DVT was diagnosed by using a duplex ultrasonographical. PE was diagnosed by multidetector computed tomographic (CT) pulmonary angiography. Patient information and clinical parameters were collected. Risk factors were analyzed by comparing the difference between VTE and non-VTE cases.The incidence of developing a DVT was 6.3% (5/80). No patient suffered PE. In univariate analysis, the mean length of hospital stay after surgery until discharge for VTE group was longer than non-VTE group, ODI scores and AIS in VTE group were significantly worse than non-VTE group, D-dimer one-day postoperatively for VTE group was significantly higher than non-VTE group. In logistic regression, D-dimer at one-day postoperatively was the only risk factor. The areas under the ROC curves for the D-dimer (post) to distinguish between non-VTE and VTE was 0.971(P value=0.000). By means of the ROC analysis, the optimum thresholds of D-dimer(post) were determined to be 9.51 mg/L. The sensitivity and specificity for the optimum threshold were 100.0% and 92.0%.The prospective study of 80 patients with spinal metastasis who underwent decompression with internal fixation revealed an incidence of DVT of 6.3%, patients with increasingly D-dimer level at one-day postoperatively had a higher risk of DVT, and the optimum thresholds of D-dimer(post) were determined to be 9.51 mg/L.

Our present study investigated whether exosome secretion of nucleus pulposus cells (NPCs) is regulated by autophagy. Different autophagic states of NPCs were induced by rapamycin (Rap), bafilomycin A1 (Baf) and other agents, and it was found that exosomes were secreted in an autophagy-dependent manner. Activation or inhibition of autophagy increased or decreased, respectively, the amount of exosomes that were released into the extracellular space. In addition, in order to confirm that Rap-promoted release of exosomes was mediated by autophagy rather than other pathways, we used autophagy associated gene 5 (ATG5) small-interfering RNA (siRNA) to silence the expression of ATG5 gene, which is indispensable for autophagy. The results showed that siRNA against ATG5 (siATG5) induced an accumulation of intraluminal vesicles (ILVs) in NPCs and a concomitant decrease in the amount of exosomes isolated from supernatant. Ras homolog gene (Rho) and Rho-associated coiled-coil forming protein kinase (ROCK) family molecules are capable of cytoskeletal remodeling and affecting vesicle transport. Therefore, we carried out targeted interventions and evaluated the effects of the RhoC/ROCK2 pathway on the secretion of exosomes within autophagic environment. Knockdown of RhoC and ROCK2 with corresponding siRNA significantly inhibited the secretion of exosomes originating from ILVs in NPCs, even when NPCs were subsequently treated with Rap. Taken together, our findings suggest that autophagy positively regulates expression levels of RhoC and ROCK2, and that the RhoC/ROCK2 pathway exerts a key function on NPCs-derived exosome secretion.

HCC stem cells were reported as posttreatment residual tumor cells that play a pivotal role in tumor relapse. Fusing dendritic cells (DCs) with tumor cells represents an ideal approach to effectively activate the antitumor immunity in vivo. DC/HCC stem cell vaccine provides a potential strategy to generate polyclonal immune response to multiple tumor stem cell antigens including those yet to be unidentified. To assess the potential capacity of DC/HCC stem cell vaccines against HCC, CD90+HepG2 cells were sorted from the HCC cell line HepG2. DC and CD90+HepG2 and DC and HepG2 fused cells were induced by polyethylene glycol (PEG). The influence of fusion cells on proliferation and immunological function transformation of lymphocytes was assessed by FCM and ELISA assay, respectively. The cytotoxicity assay of specific fusion cell-induced CTLs against HepG2 was conducted by CytoTox 96 Non-Radioactive Cytotoxicity Assay kit in vitro. At last, the prevention of HCC formation in vivo was described in a mouse model. The results of FCM analysis showed that the proportion of CD90+HepG2 cells in the spheral CD90+HepG2 enriched by suspension sphere culture was ranging from 98.7% to 99.5%, and 57.1% CD90+HepG2/DC fused cells were successfully constructed. The fusion cells expressed a higher level of costimulatory molecules CD80, CD83, CD86, and MHC-I and MHC-II molecules HLA-ABC and HLA-DR than did immature DCs (P<0.05). And the functional analysis of fusion cell-induced CTLs also illustrated that CD90+HepG2/DC fusion cells showed a greater capacity to activate proliferation of lymphocytes in vitro (P<0.05). The CD90+HepG2/DC-activated CTLs had a specific killing ability against CD90+HepG2 cells in vivo. These results suggested that CD90+HepG2/DC fusion cells could efficiently stimulate T lymphocytes to generate specific CTLs targeting CD90+HepG2 cells. It might be a promising strategy of immunotherapy for HCC.

Objective A retrospective study was designed to evaluate the effectiveness of CT‐guided core needle biopsy in diagnosing spinal lesions through comparison with C‐arm guidance. Methods From April 2013 to July 2017, a total of 188 patients, who suffered from spinal lesions or had malignant tumor history with a new spinal fracture, were included in this study. There were 96 men and 92 women, with an average of 57.1 years. A total of 238 core needle biopsies were performed. A total of 140 core needle biopsies were carried out under C‐arm guidance in 102 patients (group 1); 98 core needle biopsies were carried out under CT guidance in 86 patients (group 2); 108 core needle biopsies were performed in thoracic vertebrae, 116 were in lumbar vertebrae, and 14 were in sacral vertebrae. Seventy‐eight patients accepted surgical treatment after biopsies. For these patients, the histological pathologies of the biopsy and surgery were compared to evaluate the accuracy of the biopsy. For the other 110 patients who did not receive surgical treatment, the treatment response and the clinical course were used to evaluate the accuracy of the biopsy. The success rate, the diagnostic accuracy rate, the true positive/negative rate, and complications of the two groups were calculated and compared. Results There were no significant differences in sex, age, and lesion sites between the C‐arm guidance group (group 1) and the CT guidance group (group 2). There were no complications in the two groups. Pathological diagnoses were established in 232 of 238 biopsies. They revealed that 52 were primary malignant tumors, 12 were benign tumors, 70 were metastatic tumors, 4 were tuberculosis, and 94 were classified as “other.” The success rate of group 2 was higher than that of group 1, but it was not statistically significant (95.7% vs 100%; P = 0.098). According to the final diagnosis, the diagnostic accuracy rates were calculated and compared. There was no significant difference between the two groups (95.5% vs 96.9%; P = 0.835). The kappa coefficient was used to analyze the concordance between the histological pathologies of the biopsy and the final diagnosis in the two groups. The kappa values of the two group were 0.909 and 0.939, respectively. The results showed good consistency in both groups, but seemed better for group 2. Conclusion CT‐guided core needle biopsy is a relatively safe and effective procedure for diagnosing spinal lesions with a high diagnostic accuracy rate and few complications.

Epidural scarring occurs inevitably in the defect after spinal laminectomy, and thus how to prevent or reduce it becomes a challenging topic. In the present study, an injectable hydrogel and its dexamethasone (DEX)-loaded hydrogel systems were adopted to prevent epidural scarring in a postlaminectomy rat model. The hydrogel system composed of poly(D,L-lactic acid-co-glycolic acid)-poly(ethylene glycol)-poly(D,L-lactic acid-co-glycolic acid) (PLGA-PEG-PLGA) triblock copolymers was a free-flowing sol at room temperature, and spontaneously turned into a semi-solid gel at body temperature. A lumbar 3 total laminectomy was performed on Sprague Dawley (SD) rats, and the efficacy of the injectable hydrogel with or without drugs in preventing epidural scar formation was evaluated via the gross anatomical observation and histological examination at one month post-surgery. The results demonstrate that the use of hydrogel alone reduced epidural scarring significantly, whereas the efficacy of the DEX-loaded hydrogels presented an irregular dose-dependency of drug and even the inappropriate drug doses resulted in the negative results. Therefore, the present study confirms that the PLGA-PEGPLGA hydrogel holds potential as a barrier device to decrease peridural scarring, and reveals that the sustained delivery of the steroid hormone DEX to prevent surgery-related adhesions in the laminectomy defect is complex. Moreover, our in vivo studies also remind the researchers to pay attention to the irregular dose-dependency of the hormone drugs.

Study design This was a prospective study on the clinical outcomes of single-stage surgery for thoracic and lumbar spine tuberculosis patients with bilateral paraspinal or bilateral psoas abscesses. Objective The aim of this study was to investigate the feasibility of, indications for, and clinical effects of single-stage posterior surgery for the treatment of thoracic and lumbar spinal tuberculosis with bilateral paraspinal or bilateral psoas abscesses. Summary of background data An increasing number of articles have been published on the use of single-stage surgery for spinal tuberculosis; however, none of these articles have discussed the use of such surgery in patients with bilateral abscesses. Methods Between January 2003 and January 2011, 41 patients with thoracic and lumbar spinal tuberculosis and bilateral paraspinal or bilateral psoas abscesses were treated with single-stage posterior surgery. All of the patients were treated preoperatively with 1-2 weeks of antituberculosis drugs. All patients were managed postoperatively with standard courses of chemotherapy with triple or quadruple antituberculosis drugs. The clinical symptoms, complications, and laboratory and image indicators were recorded. Results There were no local recurrences except in one L3-L4 tuberculosis patient. Two patients presented with extraspinal tuberculosis in the third year. There were no incision complications. Bone fusion was observed 6 months after the operation. The erythrocyte sedimentation rate was normal at 3 weeks-3 months postoperatively. There were no internal fixation failures. The internal fixations in 6 young patients were removed after the spinal tuberculosis was cured. Conclusions Single-stage posterior surgery with instrumentation results in less operative trauma and can be a suitable alternative for treating thoracic and lumbar tuberculosis with bilateral paraspinal or bilateral psoas abscesses.

STUDY DESIGN A retrospective study. OBJECTIVE This study aimed to analyze the relationships between degenerative spondylolisthesis in the fifth lumbar vertebra (L5-DS) and radiographic parameters and to further determine the radiographic predictors of the development of L5-DS. SUMMARY OF BACKGROUND DATA Degenerative lumbar spondylolisthesis (DLS) is a common degenerative disease of the spine; however, the correlations between L5-DS and radiographic parameters remain controversial. PATIENTS AND METHODS This retrospective case-control study was conducted in our hospital. Between 2011 and 2014, a total of 84 subjects with L5-DS were enrolled in the DLS group, and 56 healthy volunteers were recruited to the control group. A series of radiographic parameters, including the bone mineral density, disk degenerative index, disk height, L5 vertebral size (L5-VS), lumbar lordosis angle (LL), sacral slope angle (SS), pelvic incidence (PI), facet joint angulations (FJA) of the cephalad and caudad portions, and asymmetry of the FJA, were measured in both groups by 3 examiners. RESULTS The bone mineral density, disk degenerative index, disk height, L5-VS, LL, SS, PI, and FJA exhibited significant differences (P=0.014-0.045) between the DLS and control groups. Significant changes in the FJA of the cephalad and caudad portions in the L4-L5 and L5-S1 segments were observed between the 2 groups (P=0.00, 0.00), whereas no significant differences in the asymmetries of FJA were observed in the L4-L5 or L5-S1 segments (P=0.605-0.972). Among all of the parameters, the L5-VS (P=0.025), SS (P=0.020), LL (P=0.031), PI (P=0.014), and FJA (P=0.022) were identified as being associated with the DLS group by multiple logistic regression analysis. CONCLUSIONS In this study, SS, LL, PI, and a more sagittal FJA were proven to be risk factors for L5-DS, whereas L5-VS was found to be a likely protective factor against L5-DS. These parameters should be considered predictors of L5-DS.

Objective To study the therapeutic efficacy of the “sandwich” method (medical glue + gelatin sponge + medical glue) of spinal dural repair for preventing cerebrospinal fluid (CSF) leaks during treatment of subdural tumors. Methods Fifty-four patients with spinal subdural tumors treated between April 2007 and June 2011 were retrospectively investigated. The patients were divided into two groups: a conventional group (Group A) and a “sandwich” group (Group B). The Group A patients included 16 males and 7 females with an average tumor course of 11 months (range, 2–34 months). Four of their 23 tumors were in the cervical spine, eight thoracic, and eleven lumbar. The Group B patients included 19 males and 12 females with an average tumor course of 12 months (range, 3–36 months). Five of their 31 tumors were in the cervical spines, 10 thoracic, and 16 lumbar. In Group A, the dural repairs were performed with interlocking sutures and a gelatin sponge covering the dura; whereas in Group B, they were performed with interlocking sutures, painting of medical glue around the dural incision, covering this with a gelatin sponge, and finally covering of the gelatin sponge with medical glue. The total volume of drainage after operation, incidence of CSF leaks, healing of the incision, and recovery of clinical performance were recorded. Results Compared to Group A patients, Group B patients had a significantly smaller total volume of drainage (P < 0.05) on the day of surgery, and the first, second, and third postoperative days. The incidence of CSF leakage in Group B was also significantly less than in Group A (P < 0.05). Before discharge, three patients in Group A developd hydrops, which was successfully treated by aspiration, continuous pressure from sandbags, and the prone position. During the first 3 months of follow-up, five patients developed deep hydrops under their incisions but required no treatment. There were no obvious abnormalities in Group B. Conclusion After removal of subdural spinal tumors by incising the dura mater, or in related spinal surgery, application of the “sandwich” complex to the damaged spinal dura reduces the volume of drainage postoperatively and reduces the incidence of CSF leakage.

This study was designed to compare the biomechanical effects of three posterior fixations for thoracolumbar burst fractures using the finite element (FE) method. Five T11-L1 FE models, including the intact, the fractured at T12, the monosegment fixated at the level of the fracture, the short-segment fixated with four pedicle screws and the short-segment fixated with five pedicle screws, were created. And four loading conditions (flexion, extension, lateral bending and torsion) were imposed on these models and deformations in these models under different loading conditions were calculated by finite element method. The biomechanical effects of the three different pedicle screw fixations for thoracolumbar burst fractures were compared and analyzed. The results showed that the displacement level in monosegment fixation model was close to that in the intact one. The extension motion was more limited in short-segment fixation models than that in monosegment fixation model. Under the lateral bending condition, the level of the displacements in these models were similar and the peak rotation angles in the three fixation models were close to that in the intact one. The displacements in fractured T12 were increased in monosegment fixation model under all loading conditions. These indicated that the monosegment fixation couldn’t provide desirable stability for the fractured T11-L1 and the short-segment fixation with five pedicle screws was the best selection because of ideal stability and movability.

Spinal tumors result in high morbidity and a high rate of lower limb paralysis. Both surgical therapy and radiation therapy (RT) are used to treat spinal tumors; however, how best to combine these two therapies to maximize the benefits and minimize the risks is still being debated. It is also difficult to decide the optimal timing, course and dose of RT, especially in pregnant women and children. The aim of this review is to assist surgeons who are dealing with spinal tumors by providing comprehensive information about advanced techniques for administering RT with greater precision and safety, and about the impact of various ways of combining surgery and RT on therapeutic outcomes. We here review published reports about treating spinal tumors with a combination of these two forms of therapy and attempt to draw appropriate conclusions concerning selection of optimal treatment protocols. Our conclusion is that postoperative radiotherapy, especially with high‐precision, low‐dose and multiple fractions, and brachytherapy are promising therapies to combined with surgery.

Ovarian cancer G protein-coupled receptor 1 (OGR1) has been shown to be a receptor for protons. We investigated the role of proton-sensing G protein-coupled receptors in the apoptosis of endplate chondrocytes induced by extracellular acid. The expression of proton-sensing G protein-coupled receptors was examined in rat lumbar endplate chondrocytes. Knockdown of OGR1 was achieved by transfecting chondrocytes with specific short hairpin RNA (shRNA) for OGR1. Apoptotic changes were evaluated by DNA fragmentation ELISA, electron microscopy, and flow cytometry. Intracellular calcium ([Ca(2+) ]i) was analyzed with laser scanning confocal microscopy. The mechanism of OGR1 in acid-induced apoptosis of endplate chondrocytes was also investigated. We found that OGR1 was predominantly expressed in rat endplate chondrocytes, and its expression was highly upregulated in response to acidosis. Knocking down OGR1 with shRNAs effectively attenuated acid-induced apoptosis of endplate chondrocytes and increased [Ca(2+) ]i. Blocking OGR1-mediated [Ca(2+) ]i elevation inhibited acid-induced calcium-sensitive proteases such as calpain and calcineurin, and also inhibited the activation of Bid, Bad, and Caspase 3 and cleavage of poly (ADP-ribose) polymerase (PARP). OGR1-mediated [Ca(2+) ]i elevation has a crucial role in apoptosis of endplate chondrocytes by regulating activation of calcium-sensitive proteases and their downstream signaling.

STUDY DESIGN Retrospectively study. OBJECTIVES To evaluate clinical and radiologic outcomes of skip-level anterior cervical discectomy and fusion (ACDF) with self-locking stand-alone polyetheretherketone (PEEK) cages for the treatment of 2 noncontiguous levels of cervical disk degenerative disease (CDDD). SUMMARY OF BACKGROUND DATA The use of stand-alone PEEK cages in ACDF has been proved to be safe and effective to treat CDDD. For 2 noncontiguous levels of CDDD, skip-level ACDF with self-locking stand-alone PEEK cages, which fuses only the involved levels without anterior plates, may be the optimal treatment choice. METHODS Sixteen consecutive patients with 2 noncontiguous levels of CDDD underwent skip-level ACDF with self-locking stand-alone PEEK cages. Clinical outcomes were evaluated using Japanese Orthopaedic Association scores and Odom criteria. Fusion rate and time, cages subsidence, spinal curvature, intervertebral height at the operated level, and adjacent disk degeneration were assessed. RESULTS Patients were followed up for average 43.6 months (range, 24-78 mo). The mean operative time was 113 minutes (range, 98-134 min) with an average blood loss of 62 mL (range, 47-76 mL). The Japanese Orthopaedic Association score, degree of spinal curvature, and intervertebral height were significantly increased at the final follow-up examination compared with preoperatively (P

Based on the cDNA sequence of GPX in Hyriopsis cumingii, the complete genomic DNA of GPX gene and it's 5'-flanking region were identified from H. cumingii using PCR and genome walking technique. The length of the complete genomic sequence was 6 708 bp including the 5'-flanking region, two exons, and one intron. Sequence analysis of the 992 bp 5'-flanking region revealed that it contained a core promoter element (TATA-box) and other transcription regulation elements such as AP1, C/EBP, and CdxA. The sequence lengths of the two exons were 273 bp and 991 bp, respectively, and the intron was 4 491 bp in length. Sixteen single nucleotide polymorphisms (SNPs) were detected in the GPX gene from resistant stock (RS) and susceptible stock (SS) of H. cumingii. These polymorphisms were analyzed with regard to resistance to Aeromonas hydrophila. Among them, three SNPs including A-99G, A-86C, and A-49C in GPX promoter and five SNPs including A2841T, C2847T, G3146C, A3150G, and G4645T in GPX introns were associated with resistance/susceptibility of H. cumingii to A. hydrophila, both in genotype and allele frequency. Linkage disequilibrium analysis revealed that A-86C, A-49C, C2847T, A3150G, G4645T, A2841T, and G3146C were in high linkage disequilibrium, and haplotype analysis revealed that the frequency of two major predominant haplotypes (ACTGT and TG) in the resistant group was significantly higher than that in the susceptible group. The results suggest that the polymorphic loci in the GPX gene could be potential genetic markers for future molecular selection of strains resistant to diseases.

OBJECTIVE: To study the therapeutic efficacy of the “sandwich” method (medical glue + gelatin sponge + medical glue) of spinal dural repair for preventing cerebrospinal fluid (CSF) leaks during treatment of subdural tumors. METHODS: Fifty‐four patients with spinal subdural tumors treated between April 2007 and June 2011 were retrospectively investigated. The patients were divided into two groups: a conventional group (Group A) and a “sandwich” group (Group B). The Group A patients included 16 males and 7 females with an average tumor course of 11 months (range, 2–34 months). Four of their 23 tumors were in the cervical spine, eight thoracic, and eleven lumbar. The Group B patients included 19 males and 12 females with an average tumor course of 12 months (range, 3–36 months). Five of their 31 tumors were in the cervical spines, 10 thoracic, and 16 lumbar. In Group A, the dural repairs were performed with interlocking sutures and a gelatin sponge covering the dura; whereas in Group B, they were performed with interlocking sutures, painting of medical glue around the dural incision, covering this with a gelatin sponge, and finally covering of the gelatin sponge with medical glue. The total volume of drainage after operation, incidence of CSF leaks, healing of the incision, and recovery of clinical performance were recorded. RESULTS: Compared to Group A patients, Group B patients had a significantly smaller total volume of drainage (P < 0.05) on the day of surgery, and the first, second, and third postoperative days. The incidence of CSF leakage in Group B was also significantly less than in Group A (P < 0.05). Before discharge, three patients in Group A developd hydrops, which was successfully treated by aspiration, continuous pressure from sandbags, and the prone position. During the first 3 months of follow‐up, five patients developed deep hydrops under their incisions but required no treatment. There were no obvious abnormalities in Group B. CONCLUSION: After removal of subdural spinal tumors by incising the dura mater, or in related spinal surgery, application of the “sandwich” complex to the damaged spinal dura reduces the volume of drainage postoperatively and reduces the incidence of CSF leakage.

To compare the safety and efficacies of traditional open versus percutaneous monosegmental pedicle screw fixation in the treatment of incomplete thoracolumbar spinal fracture.A retrospective analysis was conducted for 44 inpatients with a diagnosis of incomplete thoracolumbar spinal fracture (AO classification: A3.1 and A3.2) undergoing monosegmental pedicle instrumentation (MSPI) from September 2008 to January 2011. There were 24 cases in percutaneous group and 20 cases in traditional open group. The mean operative duration, blood loss, blood drainage, visual analogue scale/score (VAS) and vertebral kyphotic angle at pre- and post-operation were evaluated.No significant differences existed in operative durations between two groups (P0.05). Significant differences between two groups were observed in terms of intra-operative blood loss and VAS scores at Week 1 postoperation (P0.05). There were no significant differences in VAS score preoperation, 1 year postoperation or pre-and post-operative vertebral kyphotic angle (P0.05). No complications of iatrogenic neurological injury or hardware failure occurred.The application of percutaneous monosegment pedicle instrumentation in the treatment of thoracolumbar fractures in type of A 3.1 and A 3.2 is both feasible and safe. Its postoperative therapeutic effect is comparable to that of traditional open monosegmental fixation.

To investigate the safety and therapeutic effects of monosegment pedicle instrumentation in treating incomplete thoracolumbar burst fracture.A retrospective analysis was conducted on 56 inpatients with incomplete thoracolumbar burst fracture (AO classification: A3.1 and A3.2) from April 2005 to January 2010. There were 28 cases were fixed with monosegment pedicle instrumentation (MSPI), 28 cases were fixed with short segment pedicle instrumentation (SSPI). The operative time, blood loss, visual analogue scale (VAS) and vertebral kyphotic angle (VK) before and after surgery were evaluated.In the group of MSPI, the mean operative time was (93 ± 20) min; the intraoperative blood loss was (184 ± 64) ml; the VK angle was 17° ± 10° before operation, 7° ± 7° at one week after operation, and 10° ± 7° at latest follow-up; VAS score was 7.6 ± 1.5 before operation, 2.4 ± 0.8 at one week after operation, and 1.5 ± 0.9 at latest follow-up; no adjacent segment degeneration was found. In the group of SSPI, the operative time was (102 ± 30) min; the intraoperative blood loss was (203 ± 88) ml; the VK angle was 17° ± 9° before operation, 7° ± 7° at one week after operation, and 8° ± 5° at latest follow-up; VAS score was 6.8 ± 1.3 before operation, 3.1 ± 0.5 at one week after operation, and 1.2 ± 0.7 at latest follow-up. One case of adjacent segment degeneration was found in 36 months after operation. There were no significantly statistical differences between two groups in operative time, blood loss, VAS score and VK angle before and after surgery (P0.05). The VAS score and VK angle at one week after surgery and latest follow-up all decreased obviously than preoperative ones in both groups (P0.05).MSPI for incomplete thoracolumbar burst fracture is effective and safe. The operative blood loss, the mean operative time, the improvement of VAS score and the VK angle in group MSPI are equal to those in group SSPI.

Based on the EST sequence of mantle cDNA library of Hyriopsis cumingii, the complete cDNA of Hyriopsis cumingii GPX gene was cloned by rapid amplification of cDNA ends (RACE) in this paper. The GPX full-length cDNA sequence was 1286 bp including a 39 bp 5'-untranslated region, a 659 bp 3'-untranslated region and an open reading frame (ORF) 588 bp in length, which encodes for 195 amino acids with the predicted molecular weight of 22.2 kDa and the isoelectric point of 8.44. Molecular structure analysis revealed that GPX was Se-GPX. The amino acid sequences have three highly conserved loop structures that have a stabilizing effect on the tertiary structure of the enzyme. The amino acid sequence did not contain obvious hydrophobic domain and signal peptide. Homologous analysis of amino acid sequences indicated that the GPX of H. cumingii shared a high similarity with GPX-2 and GPX-1 of vertebrates (73.1%-80.8%), and low similarity with other types (lt; 60%). Phylogenetic trees showed that GPX of Hyriopsis cumingii was clustered together with GPX of some fishes and far away from GPX of several other published Molluscas. These results indicated GPX gene of H. cumingii cloned in this study was different from the GPX genes from other Molluscas.